Fluke MetCalUncertCalc free download

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Implementing ISO 17025 Measurement Uncertainty Requirements in Software Matt Nicholas Staff Software Engineer Calibration Division Fluke Corporation Abstract ISO/DIS 17025, "General Requirements for the Competence of Testing and Calibration Laboratories, states that "calibration certificates shall contain the measurement results including the measurement uncertainty". What is meant by that? Is it simply a Test Uncertainty Ratio (TUR) calculation, or are there other factors involved? Using the "Guide to the Expression of Uncertainty in Measurement", it certainly is more than a TUR calculation. This paper describes the implementation of the measurement uncertainty calculation in an automated calibration software package. Compliance with ISO/DIS 17025 is discussed. 1. Introduction There is an increasing need to determine measurement uncertainties in a calibration environment. This need is based on the requirement to comply with the certain standards documents, such as ISO 17025. It is no longer sufficient to calculate the traditional test uncertainty ratio (T.U.R.), per MIL STD 45662. The T.U.R. is usually calculated as: T.U.R. = (Test Tolerance) / (Accuracy of Standard) The T.U.R. calculation is thus based on the stated accuracy of the measurement standard, but does not represent the total measurement uncertainty because it does not encompass empirical information based on a sequence of actual measurements, nor does it incorporate measurement uncertainty information based on the resolution of the Unit Under Test (UUT) or other components of the measurement system and aspects of the measurement environment. This paper discusses the implementation of the measurement uncertainty calculation in MET/CAL V6.0 automated calibration software. As many MET/CAL users are aware, MET/CAL is a software product produced by Fluke Corporation. MET/CAL was first released in 1989 as an MS-DOS-based product. The initial release of MET/CAL coincided with the introduction of the Fluke 5700A calibrator. Subsequently, MET/CAL was ported to the Windows environment (V4.0), and integrated with Fluke's MET/TRACK asset management software (V5.0). The current version of MET/CAL (V6.0, August 1999) is a suite of 32-bit applications with over 50 built-in instrument drivers to support calibration standards manufactured by Fluke, Hewlett Packard, Keithley, and other manufacturers. In addition, MET/CAL includes approximately 2000 precompiled calibration verification procedures which cover a wide variety of UUTs. It is important to note that MET/CAL has always strived to maintain upward compatibility of proc